Device for measuring a torque of a rotating machine part

Abstract

A device for measuring an angle of rotation or a torque of a rotating machine part includes a radially extending bending rod secured to the machine part for joint rotation therewith, first and second sleeve-shaped bodies secured at an end of the bending rod remote from an axis of the rotating machine part, in spaced relationship to each other, each of the first and second sleeve-shaped bodies having a plurality of slots equidistantly spaced from one another and offset circumferentially relative to the slots of another of the first and second sleeve-shaped bodies, and a third sleeve-shaped body having a plurality of equidistantly spaced slots and arranged between the first and second sleeve-shaped bodies. At least one coil is assigned to each of the first and second sleeve-shaped bodies. The coils are concentric relative to each other, and their impedance change in accordance with a relative position of the slots of the first, second and third sleeve-shaped bodies, which relative position depends on the degree of bending of the bending rod.

We claim: 
     
       1. A device for measuring angle of rotation and torque of a rotating machine part, comprising a radially extending bending rod secured to the machine part for rotation therewith and defining a torsion element; first and second sleeve-shaped bodies secured at an end of said bending rod remote from an axis of said rotating machine part, in spaced relationship to each other, each of said first and second sleeve-shaped bodies having a plurality of slots equidistantly spaced from one another and arranged so that the slots of one of said first and second sleeve-shaped bodies are offset circumferentially relative to the slots of another of said first and second sleeve-shaped bodies; a third sleeve-shaped body having a plurality of equidistantly spaced slots and arranged between said first and second sleeve-shaped bodies, relative displacements of the slots of said first and second sleeve-shaped bodies with respect to the slots of the third sleeve-shaped body being defined by a degree of bending of said bending rod; and at least two coils each assigned to a respective one of the first and second sleeve-shaped bodies; said coils being concentric relative to each other, impedance of said coils changing in accordance with a relative position of the slots of said first, second and third sleeve-shaped bodies. 
     
     
       2. A device as set forth in claim 1, wherein said first, second and third sleeve-shaped bodies extend radially relative to said bending rod, the slots of said first, second and third sleeve-shaped bodies extending in a longitudinal direction of said sleeve-shaped bodies. 
     
     
       3. A device as set forth in claim 1, wherein the coils are connected in a Wheatstone bridge circuit. 
     
     
       4. A device for measuring angle of rotation and torque of a rotating machine part, comprising a radially extending bending rod secured to the machine part for rotation therewith and defining a torsion element; first and second sleeve-shaped bodies secured at an end of said bending rod remote from an axis of said rotating machine part, in spaced relationship to each other, each of aid first and second sleeve-shaped bodies having a plurality of slots equidistantly spaced from one another and arranged so that the slots of one of said first and second sleeve-shaped bodies are offset circumferentially relative to the slots of another of said first and second sleeve-shaped bodies; a third sleeve-shaped body having a plurality of equidistantly spaces slots and arranged between said first and second sleeve-shaped bodies, relative displacements of the slots of said first and second sleeve-shaped bodies with respect to the slots of the third sleeve-shaped body being defined by a degree of bending of said bending rod; and at least two coils each assigned to a respective one of the first and second sleeve-shaped bodies; said coils being concentric relative to each other, impedance of said coils changing in accordance with a relative position of the slots of said first, second and third sleeve-shaped bodies, said bending rod is a spoke of a spoke wheel secured on a rim of the spoke wheel for rotation therewith. 
     
     
       5. A device as set forth in claim 1, wherein one of said coils is located inside said sleeve-shaped bodies in a radial direction, while another of said coils is located outside said sleeve-shaped bodies.